Event Date and Time
-
Location
2208 LeFrak / Online
About the Presentation

Crime is highly concentrated in a small number of places, times, and repeat offenders, following a power-law distribution in which a small share of individuals and locations accounts for a disproportionate share of harm. Conventional discussions of crime control overlook that the most consequential spikes arise from tail risks—the small group of offenders at the extreme end of the distribution. Drawing on deterrence theory, simulations of repeat offending, and the gambler’s ruin process, this talk shows that modest increases in the certainty of sanctions for high-rate offenders can generate substantial reductions in crime. Effective policing should therefore be understood as a form of tail risk hedging, using scalable and sustainable interventions to stabilize public safety. By contrast, alternatives to policing are highly variable in quality, difficult to scale, and limited in their ability to control repeat offending, leaving communities more vulnerable to volatility in crime. Effective policing should be viewed as a form of risk management that protects against these tail risks.

About the Speaker

John MacDonald is Professor of Criminology and Sociology at the University of Pennsylvania. His research examines police reform, racial and ethnic disparities in criminal justice, and the effects of policing strategies and public policy on crime. His current work explores how urban planning can improve public health, safety, and livability in cities. Recent publications include: Where Racial and Ethnic Disparities in Policing Come From: The Spatial Concentration of Arrests Across Six Cities (Criminology & Public Policy, 2023, with Neil); Place-Based Approaches to Reducing Violent Crime Hot Spots: A Review of Public Health Evidence (Aggression and Violent Behavior, 2024, with Knorre, Mitre-Becerril, & Chalfin); and Sources of Organizational Variability in Fatal Police Shootings in the USA (Nature Human Behaviour, 2023, with Neil & Braga). Dr. MacDonald is Co-Editor-in-Chief of the Journal of Quantitative Criminology and a Fellow of both the American Society of Criminology and the Academy of Experimental Criminology.

Seminar Format

Location IN PERSON: 2208 LeFrak Hall. We are requesting advanced registration so that we can track capacity.  Please use this link to RSVP for in-person attendance.

Location ONLINE VIA ZOOM: Zoom Registration Link.  Upon registration, you will receive an automatically generated email with the direct link for the seminar.

If accommodations are needed, please send request to meeting organizer (mprc-support [at] umd.edu) at least 72 hours prior to the event, if possible, to allow time to discuss and implement alternatives.

John MacDonald Headshot